Roadside soils are regarded as a reservoir for heavy metal pollution, which potentially leads to ecosystem deterioration as well as serious hazard to human health. A comprehensive investigation was conducted for the levels, relationship with soil properties, and potential sources of heavy metals (Hg, Cu, Zn, Pb, Cd, and Cr) in roadside soils in six cities (Changzhi, Jincheng, Yuncheng, Linfen, Xinzhou, Datong) of Shanxi Province; and the corresponding ecological risk and human health risk associated with the concentrations of heavy metals were addressed. Heavy metal concentrations of 112 roadside soil samples in the surveyed cities were, in decreasing order, Zn, Cu, Cr, Pb, Cd, and Hg, which were higher than corresponding background values. The highest concentrations were in Changzhi. The results of Pearson correlation analysis demonstrated that positive correlations in varying degrees existed between soil properties such as electrical conductivity, total nitrogen, total phosphorus, and total organic carbon with specific heavy metals and that negative correlations were observed for clay and electrical conductivity. Anthropogenic sources related to traffic emissions and industrialization were the main sources of heavy metals in roadside soils according to principal component analysis. The ecological risk assessments were achieved by pollution index and potential risk index, indicating that contamination with Hg was the most serious, which posed the highest risk to the ecosystems in the surveyed cities; and the ecological risk in Changzhi ranked at the top compared with other cities. For the human health risk assessment, the results demonstrated that the noncarcinogenic and carcinogenic risks were in the acceptable range in the surveyed cities. However, there was a higher health risk from heavy metal exposure for children than adults, and the main exposure pathway was soil ingestion. In addition, Changzhi was the city with the highest noncarcinogenic and carcinogenic risks, and the main human health risks were posed by Cr contamination in roadside soil, which was different from the results of ecological risks. Both results of ecological and health risk assessment demonstrated that the higher risk exhibited in southern and southeastern cities than northern cities in Shanxi Province.

As one of the media of the ground and feet, the design of footwear products has lately received great attention, and the cushioning performance of the sole has become a key factor for the comfort and sportiness of the foot. In this paper, a new type of middle sole sports shoes with an alternating gradient lattice structure was proposed. The dynamic response of the structure was analyzed by ABAQUS software, and the model was validated by modal analysis. The effects of different kinds of alternating lattice and uniform lattice sole models on vibration isolation were analyzed by using the vibration level difference as the evaluation index of vibration characteristics. The analysis results are as follows: (a) We found that the mean of the vibration level difference of the alternating gradient structure is higher than that of the uniform lattice structure, which confirms the feasibility of the alternating gradient arrangement and its excellent buffering performance. (b) Two kinds of vibration stage drop values of the 24-series alternating lattice structure model are analyzed, and “C-G-X″ structure has the highest vibration stage drop value. In addition, the comprehensive analysis of the alternating gradient lattice structure of the soles shows that the four types of structures have good cushioning performance, and the C-series structure in the frequency range of 0–140 Hz vibration level difference value is higher than other series. The results show that the evaluation index of vibration level difference based on mechanical vibration characteristics can accurately analyze the response of different structure soles to vibration, which also provides a method for the future design of vibration reduction and exploration of the biomechanics of footwear.

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